Skeena Estuary

Oil Spill Risk if an Oil Terminal is built in Prince Rupert

The port says the risk is once every 781 years but that estimate is filled with glaring errors.

The Port of Prince Rupert (PRPA) recently hired Det Norske Veritas to scientifically estimate the risk of an oil tanker spill. The great thing about science is it can be checked against evidence. Evidence like the Amakusa grounding in July 2014.

The report estimated: “after adjusting for local factors, a tanker incident that also involved an oil or bunker spill could be expected once every 781 years” - Prince Rupert Marine Risk Assessment (PRPA). Although we can’t check that prediction against local evidence, we can check that same report’s reliability in predicting groundings and other incidents: “Based on current traffic levels and vessel mix, and after adjusting for local factors, a commercial vessel incident could be expected at a frequency of once every 23 years”- (PRPA).

Given the evidence, what are the chances this “one in 23 years” prediction is correct? In January 2012 the container ship, the Cosco Yokohama was hit by a rogue wave near Dixon Entrance, it nearly capsized and lost containers overboard, in November 2012 the Hanjin Geneva grounded right in the Rupert harbour area while piloted and in July 2014 the Amakusa with two pilots on board hit bottom, tore a gash in the hull and took on water. A rough estimate of the odds can be calculated by multiplying 1/23 by 1/23 by 1/23. A statistician would adjust that, but as it works out to one in 12,000 it is a pretty safe bet that the port’s risk assessment is very wrong.

The port is planning for the possibility of an oil tanker terminal in Rupert and they have used this flawed report as the basis for their false assurance that the risk of an oil spill is remote. The Amakusa grounding makes the last five years for Prince Rupert harbour look exceptionally bad but even without that incident Prince Rupert is known for poor anchorage and dangerous anchor dragging incidents are very common. The port's risk assessment did not include incidents related to anchoring:

"The last couple of years Prince Rupert has experienced a number of incidents because of vessels dragging anchor. These types of incidents are not included in this assessment." -page 151 see link above